Quadratic equations can be solved using the quadratic formula which is stored on the calculator and can be used from the equation mode. To do this press on ALPHA and press or the button that has X printed on top. Fx-991es plus c Fx-115s plus.
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Now lets try to do it just having the quadratic formula in our brain. So once again the quadratic formula seems to be working. You will be prompted to enter values of each of the coefficients. Ax² bx c.